Combined fire and burglar alarm



July 6, 1937. N. J. DARDEN COMBINED. FIRE AND BURGLAR ALARM Filed Aug.30, 1935 4 Sheets-Sheet l WW2??? (NW/W4 5m, i ya/ wwao Elam/M y 1937? N.J. DARDEN 2,086,405

COMBINED FIRE AND BURGLAR ALARM Filed Au :50, 1935 Sheets-Sheet 2 July6, 1937. N. J. DARDEN 8 COMBINED FIRE AND BURGLAR ALARM Filed Aug. 30,1935 4 Sheets-Sheet 5 July 6, 1937. N. .1. DARDEN COMBINED FIRE ANDBURGLAR ALARM Filed Aug. 50, 1955' 4 Sheets-Sheet 4 Patented July 6,1937 UNITED STATES PATENT OFFICE 6Claims.

This invention relates to electric signalling systems, and moreparticularly to a combined fire and burglar alarm.

Among the objects of the invention are to provide a system, the controlapparatus for which is portable and may be mounted in any desiredlocation adjacent doors, windows, or other openings, or may be placed atvarious points in storage rooms, warehouses, stores, etc., as desired;to 10 provide control apparatus made in the form of interchangeableunits, any desired number of which may be assembled to tom 9. series asrequired, to meet difierent conditions; to provide control units of thischaracter which are reversible and adaptable for use in differentpositions, according to conditions; to provide a system in which dualcircuits, extending to all points to be protected, are employed andwhich control two separate signal devices; and to provide a system 20and apparatus of the type above referred to which shall be-cheap andsimple to construct, inexpensive to maintain, and positive, efllcientand reliable in operation.

Other objects and advantages of the invention 25 will hereinafter morefully appear as the description proceeds.

In order that the invention may be readily understood, reference is hadto the accompanying drawings, forming part of this specification, and

30 in which:

Fig. 1 is a conventional view showing the signals and circuits employedin my improved system and illustrating, by way of example, the manner inwhich the invention may be applied to the pro- 35 tection of door andwindow openings;

Fig. 2 is a perspective view of one of my improved control units;

Fig. 3 is a plan view thereof, with the top opened;

Fig. 4 is a longitudinal section on the line 4-4 of Fig. 3, looking inthe direction of the arrows;

Fig. 5 is a transverse section on the line 5-5 of Fig. 4;

Fig. 6 is a transverse section on the line 6-6 of 45 Fig. 4;

Figs. 7 and 8 are fragmentary plan and sectional views corresponding toFigs. 3 and 4 but showing a slightly modified construction;

- Fig. 9 is a diagram showing in detail the elec- 5 tric circuits whichI employ;

' Fig. 10 is a side elevation showing a modified construction which maybe employed in some cases in connection with one of my improved controlunits Fig. 11 is an inverted plan of the same;

Fig. 12 is a. fragmentary longitudinal section through the meeting endsof two of my control units showing how these units may be coupledtogether; and

Fig. 13 is a detailed sectional. view showing a method of anchoring thecords employed in connection with the invention.

Referring to the drawings in detail, and more particularly first toFigs. 2 to 6 thereof, I employ as the basis of my system signal controlunits such as illustrated in perspective in Fig. 2. This control unitcomprises an elongated box case or cabinet I ,of rectangular form andconstructed of any suitable insulating material such as hard rubber,bakelite or the like. The case is provided with a top or closure formedof two sections 2, hinged to the side walls, as shown, and locked inclosed position as by means of a latch or hook 3, pivoted to one sectionas at 3* and engaging a keeper 3 on the other section.

Each end of the box or cabinet is provided with an opening 4, shown ascentrally located and preferably circular in shape.

The unit illustrated in Fig. 2 is also shown as provided with a windowin one side near one end, for a purpose which will be hereinafterdescribed.

Secured within the cabinet is a transverse partition comprising sidemembers 6 and top and bottom cross members 8, the partition beingsecured in position as by means of bolts 1 extending down through themembers 6 and the bottom of the cabinet. As clearly shown in Figs. 4 and5, this partition constitutes a frame having a rectangular opening atthe center.

Mounted on the upper and lower cross members 8 of this frame are twopairs of electrical contacts 9, l0 and II, l2. Each of these fourcontacts is substantially of U-shape, embracing the cross members 8 andsecured in position by means of bolts such as shown at 9 in Figs. 4 and5. The ends of these contact members extend horizontally at each side ofthe cross members 8, as indicated at 9 in Fig. 4, and preferably carrybinding screws by means of which the various circuit wires may beattached thereto.

Cooperating with these two pairs of contacts is a switch member in theform of a hinge comprising a base or fixed section [3 and a movablesection or arm 14 pivotally connected by means of a hinge pin IS. Thebase section I3 is rigidly anchored by means of bolts IE to a supportingblock I! at one end of the cabinet, and the arm l4 extendslongitudinally of the cabinet and through the central opening in thepartition or frame 6. A spring I8 is provided for urging the switch armabout its pivot in one direction. As shown, this spring comprises a loopof resilient wire, the mid portion of which engages the arm I! and theends are given one or more turns about the pivot pin l5, as shown atIt", and are anchored under the hinge section l3, grooves beingpreferably formed in the top of the block I! to receive them, as shownat l8 in Fig. 6. While the spring I8 is shown as disposed on the underside of the arm l4 so as to urge it upwardly, it will be readilyunderstood that by removing the hinge pin IS, the spring may be takenoff and reversed so as to bear against the upper side of the arm I andthus urge it downwardly. I provide this improved reversible arrangementbecause, under different conditions, it may be desirable to arrange thespring on different sides of the switch arm.

Secured to the switch arm l4 near its forward end are a pair of contactplates l9, preferably of copper or the like, one lying on each side ofthe arm l4 and secured thereto as by' means of rivets 20.

By reference to Fig. 5, it will now be seen that these contact plates l9are adapted to engage and bridge the pairs of upper and lower contacts9, i0 and H, |2.

Attached to the end of the switch arm I, as by means of an eye-bolt 22is a combustible cord 2| which, as shown in Fig. 4, extends down throughan opening 23 formed in the bottom of the box or cabinet. A similaropening 24 is formed in the top of the cabinet so that, when the springI 8 is reversed as described, the cord 2| may also be reversed and willpass out through the hole 24.

I contemplate extending this cord 2| across a door, window or otheropening to be protected, and securely anchoring the same at its freeend, as by means of the device shown in Fig. 13. This device comprises ascrew eye 25, adapted to be screwed into the wall, door or window frame,window sill or the like. The end of the cord 2| is attached to thisscrew eye, and the screw eye is then enclosed by means of a cap 21,having internal threads engaging an externally threaded block 26 throughwhich the screw eye passes. In some cases, this screw cap 21 may beomitted.

Mounted on the inside of the end walls of the box or cabinet are dividedporcelain clamps orcleats 28 secured by bolts 29 and adapted to hold theinsulated conductors constituting the circuit wires used in connectionwith the control units. Preferably these insulating clamps are arrangedone on each side of the opening 4, as shown.

As mentioned in the preamble and asshown in Fig. 1', I contemplateemploying a series of my improved control units in connection with theprotection of window openings and the like, and in order to firmlycouple these units together and protect the circuit wires passing fromone to the other, I preferably employ the coupling device shown in Fig.12. This coupling device comprises a hollow tubular bolt 30, having onone end a flange 3| and having the other end threaded and adapted toreceive a nut 32. This hollow bolt is passed through openings 4 in theend walls of adjacent units and i, so as to lock them together, and thewires are led through the hollow bolt, as shown in Fig. 12. From theforegoing, it will be understood that with the spring I8 and cord 2|arranged as shown in Fig. 4, the tension on the cord serves to maintainthe arm I4 in the position illustrated, in

which it engages and bridges the lower contacts ii and 2. Should thiscord 2| be severed as by being burnt or broken, the spring II willimmediately swing the switch arm I upwardly until the plate it engagesand bridges the upper contacts 9 and III. In order to make it impossibleto restore the switch arm to its original position by means outside ofthe cabinet, as for example by pulling on the cord 2|, I provide asafety catch 33, as shown in Fig. 4. This comprises a strip of resilientmetal mounted on the bottom of the cabinet and extending upwardlyadjacent the end of the switch arm I. The upper end of the catch isprovided with an oflset or shoulder 33 so arranged that it will snapover and engage under the end of the arm ll, after it has been swungupwardly, so as to lock it and prevent it from being reset in itsoriginal position. In order to reset the arm, it is necessary for anauthor ized person to open the cabinet and release the safety catch.

In order to mount my improved cabinet or control unit on a window frame,door frame or other desired support, I provide screw holes 34 in thebottom thereof, two of these screw holes being preferably locatedadjacent each longitudinal side thereof. By this arrangement, the unitmay be attached to the upper edge of the ordinary trim or moldingsurrounding a door or window opening, and either side of the unit may beso attached, as conditions may require.

Under certain conditions, as where it is desired to cut one or moreunits out of operation, I arrange to lock the switch arm down and thusprevent it from moving under the influence of spring I8, when cord 2| isdetached from the screw eye 25. For this purpose, I mount a threadedstud or post 35 in the bottom of the cabinet directly under the switcharm M, which stud or post extends through a slot 36 in the switch arm. Athumb nut 31 works on the threaded post 35 and by screwing this downagainst the arm I4, as shown in Fig. 4, the arm is locked in positionand the circuit maintained at the contacts i2. It will be understood, ofcourse, that when the control unit is in normal service, the nut 31 istaken off or at least run up to the top of the post, whereby it does notinterfere with the free movement of the arm.

For emergency signalling while the system is operating, and so as not todisrupt the protective circuits at doors and widows, I provide a controlunit in which the switch arm is not held by a cord, but is locked inposition by means of a manually releasable latch. Such an arrangement isshown by way of illustration in Figs. 7 and 8. In adapting a unit foruse with an at tachment of this kind, I provide a U-shaped bracket 51mounted just beneath the top or cover 2 of the cabinet and secured inposition by the bolts 1, which hold the frame 6 in place. The centralportion of this bracket constitutes the upper bearing for a shaft 58,iournalled at its lower end in a bearing 59, on the bottom of thecabinet and having a collar 60 engaging beneath the bracket 51 andsecured to the shaft by means of a set screw. The shaft passes upthrough the top of the box or cabinet and has a thumb nut 6| secured tothe upper end thereof, where it may be turned. Rigidly mounted on thecentral portion of the shaft is a latch member 62, placed at such aheight as to engage over the end of the arm I! and hold it down innormal position. By turning the knob 6|, the latch 62 may be swung toone side or the other, thus releasing the arm I4 and permitting thespring to move it up into engagement with the contacts 9, III. A unitequipped with a manually releasable latch of this kind is designated inits entirety by the reference numeral I Referring now to Figs. 1 and 9,the manner in which my improved control units may be utilized andoperated will be described.

In Fig. 1, I have shown a central signal station designated in itsentirety by the character A, at which station the signal devices arelocated. I have also shown, by way of illustration, 2. window B and adoor to be protected.

In the case of the window, I contemplate arranging a number or series ofmy improved control units end to end across the top of the window, asillustrated at I, P and I" in Fig. 1. In the drawings, three such unitsare shown, but it will, of course, be understood that any desired numbermay be employed. It will also be clear that I contemplate making theseunits oi. such length that the cords 2I extending therefrom andstretched across the window opening will be close enough together toprevent an intruder from entering the opening without breaking one ormore of the cords. These cords are anchored at their lower ends on thewindow sill by means of the device shown in Fig. 13.

In the case of a. door such as illustrated at C, I provide only a singlenormal control unit I, but have illustrated in connection with this unitanother unit I of the type illustrated in Figs. 7 and 8; having amanually releasable latch operated by knob 6|. By releasing this latch,emergency signals may be sent as above described.

A single cord 2| extends from the unit I across the door and is anchoredat one side by means of a screw eye 25, as above described.

Current for operating my improved system may be conveniently obtainedfrom a suitable transformer connected to ordinary alternating currentmains 38, as shown in Fig. 1. One wire 39 from this transformer, afterpreferably passing through a main switch 39*, as shown in Fig. 9, and aswitch 40 on the signal panel, is split into two parallel connectionscomprising the conductors M and 42.

In Fig. 9, the outline of the various control units I, I, I I and I asthey appear in Fig. 1, is shown in dotted lines.

The wire 4I entering the end opening of unit I passes directly throughunits I", I and I and is connected to the contact 9 in each of theseunits. From contact 9 of unit I extends a wire 43, which emerges fromthe right hand end of the unit, as shown in Figs. 1,3, 4 and 9. Thiswire 43 continues around to the door to be protected and enters theunits I and I where it is connected to the contact 9 of each.

The wire 42 entering the left hand end of unit I is attached to contactII thereof. From contact I2, this wire continues to contact II of thenext unit, and so on through the series. From the contact I2 of unit Iemerges wire 44 and this is carried on through units I and I in the sameway, emerging finally from the far end of unit I.

A third wire 45 beginning at contact III of unit l and constituting thereturn conductor, coordinated with conductor 4I, extends through allfive of the units and, after being connected with the contact I0 of eachof said units, emerges from the far end of unit I.

The wire 44 extends to the central signal station and is connected toone side of the winding of a relay 48, the other side of which isconnected by wire 49 and switch 59 to the other side or the transformer,(see Fig. 1). By reference to Fig. 9,

it will be seen that the wires 39, 42, 44 and 49 constitute a loop orseries circuit including all of the contacts II and I2 therein, eachpair of these contacts being normally bridged and con-* nected by thecontact plate I9. Thus, this is a normally closed circuit, and the relay48 is normally energized, thus holding its armature 5| in attractedposition. This armature is connected 10 with one side of a battery 54,the other side oi! which is connected by a wire 52 with an electric bell53 or other audible signal. The other side of this bell is connected bywire 52 with the back stop of the armature 5|. above described closedcircuit is broken at any point, as by means of the plate I9 moving awayfrom the contacts II and I2, the relay 48 is de-energized and thearmature 5| moves over against its back stop and closes the bellcircuit, thus sounding an alarm.

The wires M and 43, together with the wire 45, provide, on the otherhand, a normally open circuit to which all of the pairs of contacts 9and III of the various units are connected. in multiple.

This open circuit is co-extensive with the closed circuit abovedescribed and, like it, passes by all of the points to be protected.

At the central signal station, the wire 45 is connected to one side of alamp 55 or other visible signal, the other side of which is connected bywire 56 through the bell 53 and wire 5I5 to the wire 49 extending to theother side of the transformer. Thus, whenever any pair of contacts 9 andIII are closed or bridged, as by the contact plate I9 moving intoengagement with them, the open circuit above described is closed and thelamp 55 lighted. The current flowing through this lamp also flowsthrough the bell 53 and assists in operating it. This is desirable incase the battery 54 should not be in good condition, or if the opencircuit should fail.

It will thus be seen that upon the breakage of any one of the cords 2|due to force or fire, the

plate I9 will move from the position shown in full lines at I in Fig. 9to that shown in dotted lines, thus simultaneously breaking the closedcircuit at the contacts I I, I2 and closing the open circuit at thecontacts 9, I9. By this dual circuit arrangement, the relay 48 isde-energized, the 50 bell circuit closed through the battery and at thesame time current from the transformer is sent through both the lamp andthe bell, thus insuring both a visible and audible signal.

In connection with the lamp 55, I now wish to point out what I regard asan important feature of the system. This lamp is preferably of smallwattage and low voltage, and I connect it as shown in Fig. 9 in parallelwith two or more shunts 41. ably proportioned to that of the lamp inaccordance with the voltage of the transformer so that the currentflowing through wires 45 and 56 will divide,-part going through the lampitself and part By properly proportionthrough the shunts 41. ing theresistance of these shunts, the lamp will be given the voltage for whichit is designed. Should the lamp become broken or burnt out, the shuntswill still maintain the circuit intact So that it will function the sameas before.

470 In the drawings, I have also illustrated the use of a small lamp, asshown at 46 in the control unit I, this lamp being so located as to bevisible through the window 5. This lamp 46 is also connected in the opencircuit formed by the wire 45 Thus, when the 15 These shunts have aresistance suit 50 and, like the lamp 5!, is also provided with shunts41. These shunts are clearly shown in Figs. 3 and 4, as well as beingdiagrammatically illustrated in Figs. 1 and 9.

In addition to protecting door, window and similar openings, as abovedescribed, I also contemplate employing improved control units as firealarm devices to be located in obscure corners or other desired pointsof buildings, stores, warehouses, etc. To this end, I provide anarrangement such as shown in Figs. and 11. To the bottom 01' one oi myimproved control units, I attach a U-shaped bracket 63, the attachmentbeing made by means of bolts 65 passing through enlarged ends 64 formedon said bracket.

A plurality of eye-bolts 66 and 61 are secured to the several sides ofthis bracket, and the cord 2! is drawn down from the unit and passedthrough two or more of the eye-bolts 81 and then anchored to one of theeye-bolts 66. The free end M or the cord, after having been knotted inthe eye-bolt, is preferably left in a frayed or unravelled condition soas to ignite easily in case of fire.

As above stated, I contemplate placing units thus equipped at any placeswhatsoever which it is desired to protect, and in order to facilitatesupporting the control unit, I preferably extend the bracket 63 to forma strap 68 provided at its end with an eye 59, by means of which theunit may be conveniently hung upon a nail or hook.

It will of course be understood that the dual circuit arrangement abovedescribed is also used when only a single control unit is employed, thecontacts 9, 50, H and i2 of such unit being connected to control theaudible and visible signals at the central station, the same asdescribed in connection with Fig. 9. It will also be understood that thevarious circuit wires extending from the central station to the pointsto be protected, and between one point and another, are preferablyenclosed in suitable conduit or armored cable in order to safeguard themagainst injury or tampering.

What I claim is:

1. Control apparatus for electric signal systems comprising a closedcabinet, 9. switch arm pivotally mounted therein, and capable of occupying either one of two positions, a. pair of circuit controlling contactsengaged by said arm when in one position, and a difierent pair ofcircuit controlling contacts engaged by said arm when in the otherposition, automatic means for swinging said arm away from the first pairof contacts and into engagement with the second pair, and meansinaccessible from outside of the cabinet for locking said arm-inengagement with sm'd second pair of contacts.

2. Control apparatus for electric signal sys== tems comprising acabinet, a switch arm pivotally mounted therein, and capable oioccupying either one of two positions, a pair of circuit controllingcontacts engaged by said arm when in one position, and a diflerent pairof circuit controlling contacts engaged by said arm when in the otherposition, means constantly tending to swing said arm away from one pairoi! contacts and into engagement with the other, and means comprising aswinging latch for locking said arm in engagement with said nrst pair ofcontacts when desired.

3. Control apparatus for electric signal systems comprising two pairs oicontacts, spaced apart, a switch arm adapted to swing between said pairsof contacts so as to engage either pair, a spring tending to urge saidarm toward a pair of said contacts, said spring being reversible, sothat it may be set to urge the arm toward either pair of contactsdesired, and releasable means serving to normally maintain said arm inengagement with the other pair.

4. Control apparatus for electric signal systems comprising an elongatedcabinet, a switch arm pivotally mounted near one end and extendinglongitudinally thereoi', two pairs of contacts, spaced apart, betweenwhich said arm is arranged to swing, a cord under tension attached tosaid arm and operable in either oi. two directions therefrom as desired,opposite walls of said cabinet being formed with openings through whichsaid cord may pass, and a spring tending to urge said arm toward onepair of said contacts, said spring being reversible so that it may beset to urge the arm in either direction, in accordance with thedirection in which said cord extends.

5. A control unit for electrical alarm systems comprising an elongatedclosed cabinet having a transverse partition therein having an openingtherethrough, dual pairs of electrical contacts mounted on saidpartition at opposite edges of said opening and means for connectingwires 01' a plurality of electrical circuits thereto, said cabinethaving openings in its end walls for the passage of circuit wires; amovable switch member mounted in said cabinet and extending into saidopening and adapted to engage said pairs of contacts, and means forsupporting said cabinet adjacent to any opening of a building that it isdesired to protect.

6. Control apparatus for electric signal systems comprising a cabinet, atransverse partition therein having an opening therethrough, dual pairsof electrical contacts supported within said opening and means forconnecting wires of a plurality of electrical circuits thereto, a switcharm pivotally mounted near one end of said cabinet and extendinglongitudinally thereof through said opening, said arm adaptedtoswing'between and engage either of said pairs of contacts, and a cordunder tension attached to said switch arm and serving to maintain it inengagement with one pair of contacts.

NEWTON J. DARDEN.

